Punching and riveting assembly of a heat dissipater and heat conducting tubes

ABSTRACT

A method for punching heat dissipating tubes to fins comprises the steps of arranging a plurality of heat dissipating fins in parallel; aligning the via holes of the fins; inserting a plurality of heat dissipating tubes into the through holes formed by the via holes; inserting a plurality of press rods into the recesses of the via holes; positioning the fins upon a fixture; using a plurality of punching plates to impact the press rods to further impact the heat dissipating tubes so that the heat dissipating tubes are clamped tightly by the walls of the via holes; and drawing out the press rods from the recesses. In another case, the press rods can be removed and the recesses are made to extend to the edges of the fins and the punching plates punches the heat dissipating tubes directly.

FIELD OF THE INVENTION

The present invention relates to heat dissipation, and in particular toa method for punching heat dissipating tubes to fins and the deviceformed by the method, wherein oil is removed after shaping of the finsand thus it is not affected the punching process. Thereby the punchingis completed to all the fins so that the punching times are reduced andthe fins and heat dissipating tubes will not be destroyed.

BACKGROUND OF THE INVENTION

One prior art about the heat dissipation of central processing unit isformed by a plurality of fins. Heat of the fins are dissipated byflowing air into the fins.

In another prior art, a plurality of heat dissipating tubes areinstalled into the fins. This prior art is used to a compact space whichis not suitable for installing with a fan.

In one prior art, the welding material is used to combine the heatdissipating tube to the wall of the via hole of the fin and then theyare placed in a vacuum oven for heating so that welding material willpermeate into the gaps between the heat dissipating tubes and the viaholes. However the cost of the oven is high and time period is long sothat the yield rate is low. Furthermore, the welding material willpollute the environment and harm human bodies.

With reference to FIG. 1, a prior art is illustrated. Each fin 10 has aplurality of via holes 12 and then the heat dissipating tubes 11 areplaced into the via holes 12. Each time only one fin 10 is installedwith the heat dissipating tubes 11. The fin 10 is punched so as totighten the heat dissipating tubes 11 to the via holes 12. Then anotherfin is installed with the heat dissipating tubes 11 and the process isrepeated.

However the punching process will generate gaps between the heatdissipating tubes 11 and the via holes 12, see FIG. 2. The yield ratiois low and the heat dissipation from the heat dissipating tube 11 to thefin 10 is affected. The punching process is performed one by one, andthus the punching process will destroy the fins and heat dissipatingtubes.

Furthermore, in the punching process, oil is added between the heatdissipating tubes and the walls of the via holes. The oil will permeateinto the combining surfaces so that the material of the heat dissipatingtubes will oxidize to increase the heat resistance of the combiningsurface and the heat dissipation ability is reduced.

SUMMARY OF THE INVENTION

Accordingly, the primary object of the present invention is to provide amethod for punching heat dissipating tubes to fins and the device formedby the method, wherein the oil is removed after shaping of the fins andthus it is not affected the punching process. Thereby the punching iscompleted to all the fins so that the punching times are less and thefins and heat dissipating tubes will not be destroyed.

To achieve above objects, the present invention provides a method forpunching heat dissipating tubes to fins comprising the steps of:arranging a plurality of heat dissipating fins in parallel; wherein eachof the fin having a plurality of via holes; each via hole having arespective slot; each via hole having an annular wall protruded from therespective fin; aligning the via holes of the fins so that the pluralityof fins are formed with a plurality of through holes formed by via holesat the same positions of the fins; inserting a plurality of heatdissipating tubes into the through holes formed by the via holes;wherein each via hole only receives one heat dissipating tube; a size ofeach heat dissipating tube is smaller than that of each via hole so thata gap is formed between the heat dissipating tube and the respective viahole; inserting a plurality of press rods into the recesses of the viaholes; positioning the fins upon a fixture; using a plurality ofpunching plates to impact the press rods to further impact the heatdissipating tubes so that the heat dissipating tubes will collide thewalls of the via holes so as to deform and then the heat dissipatingtubes are clamped tightly by the walls of the via holes and the contactareas between the walls of the via holes and the outer walls of the heatdissipating tubes are enlarged so that the heat dissipation of the finsare increased; and drawing out the press rods from the recesses.

In another embodiment, the recesses can be extended to edge of the finsand no press rod is used. The punching plates punch the heat dissipatingtubes directly so that the heat dissipating tubes are deformed totightly engage with the walls of the via holes.

The various objects and advantages of the present invention will be morereadily understood from the following detailed description when read inconjunction with the appended drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of the prior art fins.

FIG. 2 is an elevational view of the first embodiment of the presentinvention.

FIG. 3 is an exploded perspective view of the present invention.

FIG. 4 is a schematic view showing the assembly of the presentinvention.

FIG. 5 is a schematic view showing the impacting process of the presentinvention.

FIG. 6 is a schematic view showing the state of the present inventionafter impacting process.

FIG. 7 is an assembly view of the present invention.

FIG. 8 is an exploded perspective view of another embodiment of thepresent invention.

FIG. 9 is a schematic view about the embodiment in FIG. 8.

FIG. 10 is a schematic view showing the punching process in the secondembodiment of the present invention.

FIG. 11 is a schematic view showing the structure of the presentinvention.

FIG. 12 is a perspective view of the second embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

In order that those skilled in the art can further understand thepresent invention, a description will be described in the following indetails. However, these descriptions and the appended drawings are onlyused to cause those skilled in the art to understand the objects,features, and characteristics of the present invention, but not to beused to confine the scope and spirit of the present invention defined inthe appended claims.

With reference to FIGS. 3 to 5, the structure of the present inventionis illustrated.

A plurality of heat dissipating fins 20 are arranged in parallel. Eachof the fin 20 has a plurality of via holes 21. Each via hole 21 has aslot 22. Each via hole 21 has an annular wall 23 protruded from therespective fin 20 so as to increase the clamping force of the via holes21.

The via holes 21 of the fins 20 are aligned so that the plurality offins 20 are formed with a plurality of through holes.

A plurality of heat dissipating tubes 3 insert into the through holesformed by the via holes 21. Each via hole 21 only receives one heatdissipating tube 3. A size of each heat dissipating tube 3 is smallerthan that of each via hole 21 so that a gap S1 is formed between theheat dissipating tube 3 and the respective via hole 21.

A plurality of press rods 4 are inserted into the recesses 22 of the viaholes 21, as illustrated in FIG. 5.

The fins 20 are positioned upon a fixture 5.

Then a plurality of punching plates 6 are used to impact the press rods4 to further impact the heat dissipating tubes 3. The heat dissipatingtubes 3 will collide the walls of the via holes 21 so as to deform andthen the heat dissipating tubes 3 are clamped tightly by the walls ofthe via holes 21. Moreover the contact areas between the walls of thevia holes 21 and the outer walls of the heat dissipating tubes 3 areenlarged so that the heat dissipation of the fins are increased.

After the punching process, the press rods 4 are drew out so as tocomplete the process, see FIG. 7.

Referring to FIGS. 8 and 9, another embodiment of the present inventionis illustrated.

A plurality of heat dissipating fins 20 a are arranged in parallel. Eachof the fin 20 a has a plurality of via holes 21 a. Each via hole 21 ahas a slot 22 a. Each slot 22 a is extended to one edge of therespective fin 20. Each via hole 21 a has an annular wall 23 protrudedfrom the respective fin 20.

The via holes 21 a of the fins 20 are aligned so that the plurality offins 20 are formed with a plurality of through holes.

A plurality of heat dissipating tubes 3 insert into the through holesformed by the via holes 21 a. Each via hole 21 a only receives one heatdissipating tube 3. A size of each heat dissipating tube 3 is smallerthan that of each via hole 21 a so that a gap is formed between the heatdissipating tube 3 and the respective via hole 21 a.

The fins 20 are positioned upon a fixture 5.

Then a plurality of punching plates 6 are used to impact the heatdissipating tubes 3 through the slots 22 a. The heat dissipating tubes 3will collide the walls of the via holes 21 so as to deform and then theheat dissipating tubes 3 are clamped tightly by the walls of the viaholes 21. Moreover the contact areas between the walls of the via holes21 and the outer walls of the heat dissipating tubes 3 are enlarged sothat the heat dissipation of the fins are increased.

The present invention is thus described, it will be obvious that thesame may be varied in many ways. Such variations are not to be regardedas a departure from the spirit and scope of the present invention, andall such modifications as would be obvious to one skilled in the art areintended to be included within the scope of the following claims.

1. A method for punching heat dissipating tubes to fins comprising thesteps of: arranging a plurality of heat dissipating fins in parallel;wherein each of the fin having a plurality of via holes; each via holehaving a respective slot; each via hole having an annular wall protrudedfrom the respective fin; aligning the via holes of the fins so that theplurality of fins are formed with a plurality of through holes formed byvia holes at the same positions of the fins; inserting a plurality ofheat dissipating tubes into the through holes formed by the via holes;wherein each via hole only receives one heat dissipating tube; a size ofeach heat dissipating tube is smaller than that of each via hole so thata gap is formed between the heat dissipating tube and the respective viahole; inserting a plurality of press rods into the recesses of the viaholes; positioning the fins upon a fixture; using a plurality ofpunching plates to impact the press rods to further impact the heatdissipating tubes so that the heat dissipating tubes will collide thewalls of the via holes to deform and then the heat dissipating tubes areclamped tightly by the walls of the via holes and the contact areasbetween the walls of the via holes and the outer walls of the heatdissipating tubes are enlarged so that the heat dissipation of the finsare increased; and drawing out the press rods from the recesses.
 2. Themethod of claim 1, wherein each via hole has an annular wall protrudedfrom the respective fin to increase the clamping force of the via holesto the heat dissipating tubes.
 3. A heat dissipating device comprising:a plurality of heat dissipating fins arranged in parallel; each of thefin having a plurality of via holes; each via hole having a slot; eachvia hole having an annular wall protruded from the respective fin so asto increase the clamping force of the via holes to the heat dissipatingtubes; the via holes of the fins being aligned so that the plurality offins being formed with a plurality of through holes; a plurality of heatdissipating tubes located in the through holes formed by the via holes;each via hole only receives one heat dissipating tube; a size of eachheat dissipating tube being smaller than that of each via hole; whereinthe heat dissipating tubes are tightly engaged in the via holes bypunching.
 4. A method for punching heat dissipating tubes to finscomprising the steps of: a plurality of heat dissipating fins arrangedin parallel; wherein each of the fin has a plurality of via holes; eachvia hole has a slot; each slot is extended to one edge of the respectivefin; each via hole has an annular wall protruded from the respectivefin; aligning the via holes of the fins aligned so that the plurality offins are formed with a plurality of through holes; inserting a pluralityof heat dissipating tubes into the through holes formed by the viaholes; each via hole only receiving one heat dissipating tube; wherein asize of each heat dissipating tube is smaller than that of each via holeso that a gap is formed between the heat dissipating tube and therespective via hole; positioning the fins upon a fixture. using aplurality of punching plates to impact the heat dissipating tubesthrough the slots; the heat dissipating tubes will collide the walls ofthe via holes so as to deform and then the heat dissipating tubes areclamped tightly by the walls of the via holes; moreover the contactareas between the walls of the via holes and the outer walls of the heatdissipating tubes are enlarged so that the heat dissipation of the finsare increased.